As Colorado River Water Vaporizes in the Desert, Arizona Faces a New Energy Reality
Recently, the Navajo and Hopi Nations signed a controversial lease with the Arizona public utility, Salt River Project (SRP). Under that agreement, and for the benefit of SRP, the Navajo Generating Station (NGS)
near Page, Arizona will operate until 2044. The primary function of
NGS is to provide electrical energy to SRP’s Central Arizona Project (CAP).
Using that power, SRP lifts 1.5 million acre-feet of water per annum
from Lake Havasu. After pumping it over the Buckskin Mountains, CAP
alternately siphons, pumps and uses gravity to transport the water
east, to Pima, Pinal and Maricopa Counties.
While crossing Arizona’s Tonopah Desert, the aqueduct consists of a large, evaporation-trench. From Tempe to Tucson, the water remaining after a scorching trip across the desert might become mist at an outdoor restaurant. Burning eight million tons of Black Mesa coal each year, NGS generates more than enough power to pump a continual flood of Colorado River water across the Arizona desert.
In the event of a power shortage or a shortage of Colorado River water, CAP could economize by curtailing deliveries to both agriculture and its groundwater recharge stations. If CAP water deliveries were to fall below current per capita consumption, either new water connections would halt or consumers would face rationing and shortages. With that, Arizona’s fifty-year construction and population boom would end. With its economy reliant on new residential development and construction, Arizona's ongoing boom could quickly turn to bust.
If CAP water deliveries were to diminish significantly, the Maricopa County might face its second Great Disappearance in less than a millennium. In 899 CE, the Hohokam Indians experienced and then recovered from a flood that devastated their extensive water storage and delivery systems. In the late fourteenth century, major flooding again occurred in the Valley of the Sun. This time, recovery flagged. By 1450 CE, between 24,000 and 50,000 Hohokam Indians had disappeared from the archeological record.
Currently, the Phoenix-Tucson metropolis is living on borrowed time and borrowed water. By “borrowed time”, I mean that California, Arizona and Nevada currently withdraw Colorado River water faster than the watershed upstream can replenish it. By “borrowed water”, I mean that as shortages loom, Arizona’s CAP water rights are subordinate to those of California. Arizona’s current tourism motto is “Discover the Arizona Less Traveled”. In the years ahead, the less traveled part of Arizona may well include Pima, Pinal and Maricopa Counties.
Over mountains and desert, CAP’s borrowed water travels to an artificial oasis with a population of five million. Arizona's twenty-year development plans are a pipe dream. They call for a future Southern Arizona population of up to ten million. Long before that, the big pipe that is CAP may be running near empty. One does not need to be a climate scientist to see that sustained pumping from a declining Colorado River is not a viable long-term solution. In fact, supplying sufficient water to current users may yet prove unsustainable.
In order to transport their allotment of Colorado River water across the desert, Arizona dumps its environmental responsibilities on the Navajo Nation. From mining, processing, transport and burning of Black Mesa coal, the Navajo and Hopi Nations subsidize profligate water use in Phoenix and Tucson. When it came to producing additional power closer to home, no one in Phoenix wanted a coal-fired power station upwind. Instead, at its Palo Verde Nuclear Generating Station (PVNGS), SRP utilized a “clean power source”. Standing in the Tonopah Desert, fifty miles west of Phoenix, the massive complex comprises the largest nuclear power plant in the nation. Tonopah derives from the word Tú Nohwá, meaning "Hot Water under a Bush". In fact, PVNGS is the only major nuclear power plant in the world not situated adjacent to a major body of water.
Owned by a consortium of utilities stretching from El Paso to Los Angeles, PVNGS’s biggest advantage is that it does not burn coal. Since its initial construction in the 1970s, PVNGS has been a magnate for nearby natural-gas-fired “peaker plants”. Each of those natural gas plants consumes cooling water, emits hydrocarbons and heat into the atmosphere. Both the Black Mesa Complex (strip-mine) to the north and PVNGS have a public relations advantage. Located in remote locations, both complexes are out of sight and out of mind. Few in Arizona realize that their lifesaving air conditioning depends on a 3,900 megawatt power plant called "Hot Water under a Bush".
Other than the inherent fragility of 1970’s nuclear power plant design, the main weakness of PVNGS is its cooling loops. As the sole source for their cooling water, all of the Tonopah power plants rely on treated effluent water from Phoenix and other cities. Reduced future delivery of Colorado River water will force conservation on Phoenix. As residents curtail non-essential water usage, demand for CAP water will harden at a lower volume. Inevitably, as Phoenix consumes less fresh water, sewage plant effluent will decrease as well. I do not know how much treated water Phoenix currently has to spare, but that would be an interesting statistic.
Although currently recharged with excess CAP water, the Tonopah Aquifer is finite. If Phoenix metropolitan sewage plants currently supply most of their outflow to Tonopah, any decrease in effluent could set off an unpleasant chain reaction. If treated effluent flow decreased, the power plants at Tonopah would resort to pumping from their local aquifers. To see the negative ramifications of such an act, one needs to look no further than to the depleted aquifers of Black Mesa, to the north. Not if, but when the Tonopah aquifers run dry, power production would decrease to whatever diminished level the sewage plants upstream could support.
Pumping of groundwater at Tonopah will only delay the day of reckoning. Even today, sixty percent of Arizona's population relies on groundwater for its domestic water needs. Thus, if history is an indicator, Arizona will soon tap its desert aquifers. When the aquifers make their final retreat, CAP customers will discover a new reality. With insufficient cooling water available at Tonopah, both nuclear and gas-fired generating stations will curtail output. Unless some of CAP's then diminished supply of Colorado River water is diverted directly to the power plants, a downward spiral of SRP power production will ensue.
Any decrease in water or power deliveries would strain the economy and ultimately, the population of Southern Arizona. In subsequent years, the price of both water and power could exceed many Arizonian’s ability to pay. Unable to revert to its former ranching, mining and semi-rural economy, the outlying suburbs of Maricopa, Pinal and Pima Counties would be the first to go. Old copies of Arizona Highways Magazine might look new again. Ghost towns, like Casa Grande, Arizona could feature both Hohokam ruins and abandoned regional shopping centers, which have gone to seed. Once again, a complete way of life could vanish from the Valley of the Sun.
This is Chapter 2 of a four-part series about coal and water in the Southwest. Whether in power plants or homes, the burning of Navajo Reservation, Black-Mesa-Coal degrades lasting environmental and health effects created by the burning of Black Mesa coal in both power plants and homes on the Navajo Reservation, Read Chapter 3.